Vibration dampening fitting



. 9, 1941'. c. M. HAMBLINY VIBRATION DAMPENING FITTING Filed Aug. 6, 1940 INVENTOR CL V05 M HAMBL //V.

ATTORNEY Patented Dec. 9, 1941.

UNITED STATES PATENT OFFICE vIBnArIoNpAMrENmG FITTING Clyde M. Hamblin, Washington, 1). 0.

Application August 6, 1940, Serial No. 351,637

2 Claims. (01.248-358) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O. G. 757) This invention relates to improvements in the design of vibration dampening fittings.

It is a principal object of this invention to provide means or supporting a load by a tubular member of elastic material, such asrubber, in shear between an outertubular member and an inner tubular, cylindrical or regular poly- V hedral member. 7 p

A further object is to provide an elastic material such as rubber in tubular form with tubular outer casing and tubular, cylindrical or regular polyhedral central insert in considerable lengths from which sections of desired length may be cut to make up vibration dampening fittings having the required vibration dampening characteristics.

Another object is to provide means of making up any selected length of the tubular elastic material together with its inner and outermembers with standardized end fittings to form a complete vibration dampening fitting.

In accomplishing these and other objects there are provided the improved details of construction, the preferred forms on which are illustrated in the accompanying drawing, wherein Fig. 1 is a longitudinal sectionalview of a portion of a tube of elastic material, taken on line l-i of Fig. 2;

Fig. 2 is a transverse sectional view of shown in longitudinal section by Fig. 1;

Fig. 3 is a longitudinal sectional view of a portion of a tube of elastic material with tubular metal outer casing and solid metal central insert taken on line 3-3 of Fig. 4;

Fig, 4 is a transverse sectional view of the tube shown in longitudinal section by Fig. 3;

the tube Fig. 5 is a longitudinal sectional view of a por- Fig. 11 is a sectional view in elevation of a vibration dampeningfitting arranged for supporting a load from below with point 01 attachment to the load below the vibration dampening element; and. V I

Fig. 12 is a sectional-view in elevation of a vibration dampening fitting wherein the elastic material is cut to a longer length than the enclosing tube.

There is shown at 20 in Figs. 1 and 2, a section of tubing 0! elasticv material, such as rubber,

"with hollow core 2|.

In Figs. 3 and 4, the elastic tube is molded in or inserted in an outer tube or pipe 22, preferably metallic tube or pipe of standard commercial size. A solid core 23, preferably metal bolt material of commercial standard size, is molded or inserted centrally of the elastic tube. The solid core 23 may have a smoothsuriace or may be threaded its entire length with standard threads. The elastic tube I20 may be bonded to the outer tube 22 by cementing or vulcanizing or may be a close fit without bond. The solid core 23 may likewise be bonded to the interior of the elastic tube I20 by cementing or vu1canizing or may be a close fit without bond.

In Figs. 5 and 6, the elastic tube 220 is molded in or inserted in an outer tube I22 as described for Figs. 3 and 4. A tube or pipe core I23 is substituted in Figs. 5 and 6 for the solid core 23 shown in Figs. 3 and i.

The elastic tube with its outer metal tube and inner metal core may be of anylength convention of a tube of elastic material with tubular metal outer casing and tubular metal central insert taken on line 5-5 of Fig. 6;

Fig. 6 is a transverse sectional view of the tube shown in longitudinal section by Fig:5;

Fig. 7 is a sectional view in elevation of a vibration dampening fitting arranged for suspending a load from overhead;

Fig. 8 is a plan view of the fitting shown in Fig. 7, taken on line 8-- 8;

Fig. 9 is a sectional view in elevation of a vibration dampening fitting arranged for supporting a load from below with point of attachment tothe load above the vibration dampening element;

Fig. 10 is a plan view of the vibration dampening fitting shown in Fig. 9 taken on line Ill-l0;

lent for manufacture but is preferably of commercial pipe or tube length. The elastic material and the treatment or cure thereof must be such as to give proper vibration dampening characteristics. The load bearing and vibration dampening characteristics of the elastic material are dependent upon the treatment or cure of the material, the transverse sectional area of the material and the longitudinal length of the material. As one of the features oi'this invention is the ability to cut the tubular elastic material to anay desired increment of length. the number of different treatments or cures of the elastic material and the number of different sizes of transverse sectional area of the elastic material may be relatively few, since a large variation in loading can be accommodated with a given quality and transverse sectional size of elastic material by selection of the proper length of elastic material.

In the view of an assembled vibration dampening fitting shown in Fig. 7, the elastic tube due to the load and to 324 with its outer metal tube 222 and inner metal tube 223 is cut to desired length. The

outer metal tube 222 is threaded on the. ends and threaded retainers 26 and 21 arescrewed hard up against the ends of tube 222 and elastic tube 329. Retainer 26 has a hole concentric with the axis of the elastic tube and retainer 21 has a,

threaded tubular elongation 29 oireduoed size,

concentric with the axis of the elastic tube and projecting through a hole 39in bracket 24. The vibration dampening fitting is secured in place in bracket 24 by means of nut 3| screwed on the threaded elongation 29 of retainer 21. Hole 39 in bracket sired. Threaded stud 32 is inserted in inner tube 223 and threaded nuts33 and 34 are'screwed hard up against the ends of inner tube 223 and elastic tube 329. Edges 35 and 36 of retainers 26 and 21 and edges 31 and 38'of nuts 33 and 34 to prevent cutting the surface of the elastic ma- 1 terial when it is deflected by the load. Where the-load is suspended from a portion 39 of nut 33 is extended radiallyto engage with the lower end of failure of the elastic overhead, as in Fig. 7,

oi retainer 26 in case material 320 which might cause the load to fall. r

The radial width of space 40 between retainer 26 and nut "33and space 4| between retainer 21 and nut 34 lsmad suitable to permit the necessary deflection of the elastic material in shear The upper end of through hole 42 in dampening characteristics. threaded stud 32 is inserted structural member 43, from stud '32 for additional purposes the type of elastic material, exterior tube and solid core construction shown in Figs. 3 and 4 are used in Figs.9 and 10, but the construction shownin Figs. '5 and 6 and usedin Figs. '1 and 8 is equally suitable. In Fig. 9 standard nuts I34 and washers 45 are substituted for special nuts 33 and 34 "shown in Fig. 7. The elongation I29 ofretainer I21 is screwed into floor flange 46' to support the entire assembly. The load I25 is supported by bracket I24 on central-stud I32which is threaded through hole I30 in bracket I24 and is secured by nut I.

The vibration dampening fitting shown in Fig. 11 is generally similar to those shown in Figs. 7 and 8, but is arrangedfor supporting load 225 from below as on a floor or deck, and has the vibration dampening element above the point of attachment to bracket 224 instead ofbelow, as in Fig. 9. In this arrangement elongation 229 of retainer 221 is threaded through hole230 in bracket 224 from above and is secured by nut' [31. The assembly is supported on the floor or and 11, except that 24 may be threaded to flt threads on elongation 29 for additional security, if de-' are rounded in way of the elastic material 9 factured and/or. used of this invention,

give the desired vibration which the load 25 l is supported, and securedby nut.44. The hole deck by stud 232 which is screwed into floor flange I46. This arrangement has the advantage that the elastic elements 01' the vibration dampening fittings at different points of support for a given load such as a fan, pump or other machine may be of difierent lengths to suit unequal loads at the respective points without aflecting the level of the machine.

Fig. 2 shows a vibration dampening element generally similar to those shown in Figs. '7, 9 the elastic tube 629 is cut longer than the outer tube 522 and inner tube I23, if fitted, to permit modifying the vibration dampening. characteristics of the elastic material by compressing the material by means of threadedretainers 326 and 321- and nuts 334.

Other modifications and changes in the proportions and arrangements of the parts may be made by those skilled in the art without departing from the nature of the invention within the scope of'what is hereinafter claimed.

The invention described herein may be manuby or for the Government of the United'States of America for governmental purposes without the payment of any royalties thereon or therefor.

Having thus set forth and disclosed the nature what is claimed is:

1. A vibration dampening fitting comprising a selected length of elastic material of uniform tubular shape, a rigid tubular'outer casing, a rigid inner con-centric core, the opposite ends of said casing and of said core being externally threaded, said core threads extending to within said length of tubular elastic material to frictionally retain said elastic material thereon,

threaded nuts cooperating with said threaded ccre, threaded retainer caps cooperating with said threadedcasing, said caps having internally I bular shape, arigid tubular outer extending flanges holding said elastic material within the ends of said casing, and a supporting means for said fitting comprising a concentric tubular elongation extending from one of said cap flanges.

' 2. A vibration dampening fitting comprising a selected length of elastic material of uniform tucasing, a rigid inner concentric core, the opposite ends of said casing and of said core being externally threaded, said core threads extending to within said length of tubular elastic material to frictionally :"retain said elastic material thereon, threaded nuts cooperating with said threaded core, threadedretainer caps cooperating with said threaded casing, said caps having internally extending elastic material within the a supporting means for said a concentric tubular elongaends of said casing, fitting comprising tion extending from one of said cap flanges, and

a load assuming support in case of failure of said elastic material comprising a radial flange on the outer end of said nut at the opposite end from said tubular elongation, said radial flange being of greater diameter than the diameter of the opening in the flange of said adjacent cap.

CLYDE M. HAMBHN. 

